With the increase in awareness of management of information such as personal information in recent years, the electronic devices having a security function have started to be widely used In the security function, a person wishing to access information is subjected to an authentication check to determine whether the person has been given permission to access the information.
Among proposed methods for authenticating a person such as fingerprint authentication, vein authentication, and face authentication, iris authentication is regarded as a promising method due to its high acceptance rate and easy user operation for authentication. In the iris authentication, an image of iris regions existing around the pupils of a person is taken by a camera, and authentication is thereafter performed. For example, Japanese Laid-open Patent Publication No. 2006-181012, Japanese Laid-open Patent Publication No. 2006-48266, Japanese Laid-open Patent Publication No. 2008-197713, Japanese Laid-open Patent Publication No. 2005-253778, and other documents disclose related arts.
However, if a mobile terminal such as a smartphone is provided with the iris authentication function, there is a necessity to take an image of the face of a user of the mobile terminal before using the mobile terminal, for example, by a camera incorporated in the mobile terminal to thereby acquire an image of the iris regions of the user.
If the iris authentication is performed with a person other than the user being present near the mobile terminal, for example, in a store or a train, it is conceivable in some cases that the action of taking a photograph of the iris regions of the user causes the person near the user to misunderstand that the user is taking a sneak photograph, that is, taking a photograph of the person other than the user is taken without permission.
A misunderstanding where such an action is misunderstood as sneak photography may occur not only when authentication such as the iris authentication is performed but also when the user takes a photograph of the user himself/herself with the mobile terminal held with his/her hand, that is, when a so-called “selfie” is performed. When the user takes a self-portrait, it is desirable to reduce the likelihood of such an action being misunderstood as sneak photography.